How Classification Works

Overview

Classification assigns every medical device to one of four classes — Class I, IIa, IIb, or III — based on risk, invasiveness, and duration of contact. It is the manufacturer's responsibility, applied using MedDO Annex VIII. The class drives the conformity assessment route and Swissmedic registration requirements.

The Four Classes

Class	Risk	Examples
Class I	Low	Bandages, non-sterile surgical instruments, wheelchairs
Class IIa	Medium-low	Blood glucose monitors, ultrasound equipment
Class IIb	Medium-high	Ventilators, orthopaedic implants, contraceptive devices
Class III	Highest	Drug-eluting stents, transcatheter heart valves, active implantables

Class I sub-types: Im (measuring function), Is (supplied sterile), Ir (reusable surgical instruments).

The 22 Classification Rules

MedDO Annex VIII Part II contains 22 rules organised by device type:

Rules 1–4: Non-invasive devices
Rules 5–8: Invasive devices
Rules 9–13: Active devices
Rules 14–22: Special rules (software, nanomaterials, combination devices, spinal, etc.)

See MedDO Classification Rules 1–22 for full detail on each rule.

The Highest-Class Rule

If multiple rules yield different classes, the device is assigned to the highest class. This prevents under-classification of multi-function devices.

Practical Classification Steps

Define the intended purpose precisely (patient population, body contact, duration, active/non-active)
Work through all 22 rules — flag every rule that could apply
Apply the highest-class rule where multiple rules apply
Document the classification rationale in technical documentation
Review classification whenever intended purpose or design changes significantly

Official Sources

Disclaimer

AI-assisted content for navigation only. Always verify against official Swissmedic and Fedlex sources. Not legal or regulatory advice.

Overview​

The Four Classes​

The 22 Classification Rules​

The Highest-Class Rule​

Practical Classification Steps​

Official Sources​

Related Pages​